The game proved to be one of the most anticipated and popular computer game releases ever, with 4.5 million units shipped to retail stores and over one million units sold within a month.[4]Warcraft III won many awards including "Game of the Year" from more than six different publications.[5]

One of the main innovations Warcraft III offers over the previous games in the series is the way the role of hero units has changed. Where before, heroes were merely very powerful variants of standard units, now they are unique, with their own special abilities that normal units do not have access to. For instance, heroes within the game can find or trade items to increase skills, defense, etc. With each kill of an enemy of a certain level the heroes gain experience points, eventually resulting in increased levels of their own, and new spell options (thus introducing role-playing game elements to the series).[6] Some heroes also can apply beneficial auras to allied units.

Another new innovation is the addition of creeps, which are computer controlled characters the player fights even in multiplayer. They guard key areas or neutral buildings and are designed to act as a resource for the players to kill to provide experience points to a player's hero and to provide hero items. The idea is to force the player to be aggressive instead of "turtling up" (building up powerful defenses and rarely attacking).[7]

Players meet other players over the Internet to set up multiplayer games via Blizzard's free Battle.net service, or may play against the computer.[10]

Warcraft III also includes a very thorough scenario editor called World Editor. It uses a scripting language similar to the trigger system used in Starcraft. As well as providing the ability to edit any aspect of the units, buildings and spells, it has such advanced features as custom tilesets, custom cinematic scenes, dialog boxes, variables, and weather effects. Many custom maps, featuring a large variety of gametypes continue to be developed, and together with the expansion pack have contributed to the longevity of the game.[11]

The young Thrall awakes fom a strange vision, directing him to the prophet Medivh. Medivh tells him to rally the orcs from Lordaeron and travel to Kalimdor, where they shall meet their destiny. He frees the orcs from the remaining internment camps, including Grom Hellscream. The Horde steals the human fleet from Southshore and sail off. Near the Maelstrom, they are forced to land on a small island to repair their ships. There they are joined by the Darkspear Trolls, led by Sen'jin, but are soon ambushed and captured by a group of murlocs worshiping a Naga Sea Witch. Thrall and his people need to escape from their underworld prison together with the trolls and flee from the island before it is destroyed by an erupting volcano.

Prince Arthas, a paladin of the Silver Hand, The Captain and Jaina Proudmoore, Arthas' former lover and apprentice-Archmage, are investigating a strange plague that is spreading across the lands of Lordaeron. To their horror, they find that the plague turns unsuspecting people into hideous Undead warriors, and must move to stop the undead's plans. After a string of hollow victories (many towns in the now Plaguelands being destroyed), Arthas decides that the best way to end the game was to destroy Mal'Ganis the (supposed) leader of the scourge. Mal'Ganis travels northward to the icy lands of Northrend, and Arthas follows him. There he aids an old friend, Muradin Bronzebeard, who tells him of a powerful weapon, a sword called Frostmourne. Arthas obtains Frostmourne, at the (supposed) cost of Muradin's life, and uses it to defeat Mal'Ganis. However, as a result, Frostmourne steals Arthas' soul and turns to ally the undead...

With their new leader, the undead must move to complete their purpose in Lordaeron, which is to destroy the remnants of the Alliance and pave the way for a new invasion. In a series of quests, Arthas succeeds in reviving a former adversary, Kel'Thuzad, as a Lich, and the two successfully open an inter-dimensional portal for the true masters of the Scourge, the Burning Legion, to enter the realm of Azeroth (see the article on Arthas for a more detailed description).

After escaping Human captivity and fleeing to the shores of Kalimdor, orcish warchief Thrall must lead his brethren to safety and ensure their survival in this strange and hostile land. Help comes from the Tauren, a nomadic group of Kalimdor natives, and their leader, Cairne Bloodhoof. Unfortunately, fellow orc Grom Hellscream falls under demonic corruption, and Thrall is forced to ally himself with Jaina Proudmore, now leader of the survivors of Lordaeron. He also discovers (courtesy of an oracle) that his fate is to help repel the Burning Legion, and he and Jaina accomplish this goal, and also to save Hellscream. Afterwards, Grom insists upon battling Mannoroth, the demon who cast him into the corruption. Thrall and Grom succeed in vanquishing Mannoroth, but Grom is slain in the process.

With the coming of the undead and Burning Legion as well as the humans and orcs, Tyrande Whisperwind and her night elf Sentinels fight a desperate battle to save their beloved home of Kalimdor. She first reawakens her lover, Malfurion Stormrage, and then the Druids of the Talon and finally the Druids of the Claw. She also decides to free the great betrayer, Illidan Stormrage, and he is eventually instrumental in weakening the Legion. Finally, she and Furion join forces with Proudmoore and Thrall to delay the Legion's advance until a proper end can be arranged for their leader Archimonde (mirroring the final mission of Starcraft, in which the player commands a multi-racial force against a common foe).

Unlike other RTS games, Warcraft III has introduced a new element of game play, special units called heroes, they are super units that have special abilities that expand as the game progresses (as they gain experience).[6] For example, an Archmage hero can acquire the ability to (temporarily) summon water-elementals, increase the mana regeneration rate of surrounding magic casting units, create a blizzard over enemy units, and teleport friendly units to other parts of the map. In the course of a game a maximum of up to three heroes can be built, but if they die, they can be revived at an altar.

The upkeep is a gameplay concept that keeps armies small as it penalizes anyone who gets big too fast. With the Heroes occupying five food cap and the upkeep that force you to have low food cap it is difficult to win through sheer numbers, and micromanagement becomes more important, as a result the gameplay is more tactical than strategical.

There are strong distinctions in the game between melee and ranged units; between air and ground units; and (particularly in Warcraft III: The Frozen Throne) between mundane, magical, and antimagic units. Antimagic units, such as the Spell Breaker (only in the expansion pack) and the night elves' Dryad, have the ability to cancel the effects of magic spells cast on other units.

The strategy board game Warcraft: The Board Game was released in 2003 by Fantasy Flight Games, and is based on Warcraft III. It uses a modular game board, which allows many different scenarios to be played with the same set of components.

On May 29, 2003, Blizzard announced that the expansion set, Warcraft III: The Frozen Throne had "gone gold" (release version sent to presses). It was released in stores worldwide in multiple languages beginning on July 1, 2003. It includes an additional hero for each race and three to four new units per race, four campaigns, eight neutral heroes, the ability to build a shop and various other improvements such as the ability to queue upgrades. It requires the ownership of Reign of Chaos. Blizzard regularly patches both the original game and the more popular "expanded" version to fix bugs, add new features, and balance multiplayer play. The latter is the reason Blizzard games remain popular long after their initial release.

A massively multiplayer online role-playing game set in the Warcraft universe, entitled World of Warcraft, is the fourth Warcraft game in a series produced by Blizzard. It picks up the Warcraft storyline four years after the events of Reign of Chaos.

One of the features of Warcraft III, like Warcraft II, are the unit quotes. If a single unit was clicked several times in a row, the unit's voice samples would change. The unit would start getting angry at the player, or start saying silly things in reference to movies, games, or other things. For example, a peasant might say, "Help! Help! I'm being repressed!" — a quote from the movie Monty Python and the Holy Grail or a Crypt Fiend might say "Spider sense...tingling" - an oft-quoted line of Spider-Man.

Warcraft III: Reign of Chaos started as a "Role-Playing Strategy": A strategy game set heavily within a role-playing environment. Having smaller, potent parties of heroes and troops in a dynamic world of living towns, wandering monsters, characters and quests, while simultaneously devising strategies to defeat their enemies.[13] However, during the develpment, many of the RPS ideas were scrapped and became an RTS with some RPG elements.

There are many player-made multiplayer maps (made with World Editor, which can be used to make your own levels, even fan-made campaigns, that comes with the game) available for download and play on Battle.net as well as many fansites.

The DOTA map genre consists of PvP gameplay where two teams of heroes support their respective AI-controlled armies in large-scale battles. It is based on the wildly popular "Aeon of Strife" Starcraft map, although the original consisted of players cooperating against a single AI-controlled army. Of the maps spawned under the AoS genre, "Defense of the Ancients" is one of the most popular in Warcraft III. Because the original AOS was a Starcraft map, and because of DOTA's own popularity, it has become the de-facto standard for this genre of custom map.

A map originally created by Guinsoo, now maintained by IceFrog. Based on the original DotA by Eul.

Tides of Blood

Renowned for its unique "Blood Mage" hero that utilized triggering and special effects to create some impressive visuals for spells.

Farmer vs. Hunter or "Tag"

A farmer makes farms at the start and eventually powerful towers, while the hunter must find farmers and kill them before their bases become too big. Tag games often pit the players against an AI-controlled hunter. There are innumerable variations on this theme, inspired by the old "Cat and Mouse" StarCraft maps.

Sheep Tag

There are many different variations on the basic Sheep Tag formula, such as Panda Tag, Tauren Tag, Tree Tag, and Jailbreak (not to be confused with Prison Escape).

Footman Wars

The "Footman Wars" genre of games is based on the old "massing" games of StarCraft, where players are given absurdly large quantities of units at given intervals, and can send them out to engage in massive conflicts. The map designs are usually fairly simple.

Lord Of The Rings-based games, such as those based on famous battles of the fictional War of the Ring and Helms Deep.

Minigames

In the "minigame" map genre, mapmakers use clever triggering to create a variety of minigames for players to enjoy (a la Mario Party).

Pyramid Escape, where players must work together to overcome a series of challenges, including a "Pac Man" game, a quiz show based on "The Weakest Link," and even a miniature AOS/DOTA.

A map genre akin to The Sims, where players take control of a character responsible for working a job, attending school, and other "real life" activities. The original Real Life maps spawned dozens of spin-offs that added and built upon the original concept.

Life of a Peasant and spin-offs (over 300 versions exist)

One of the most popular RL maps is LOAP, which came to replace the original "Real Life" as the benchmark of the genre.

This genre includes maps such as Line Tower Wars, XTD, Cube Defense, Green TD, Blue TD, and Massacre TD. The basic concept consists of players constructing towers to defend against waves of enemies. Blizzard made two of their own TD maps, one of which was a bonus level in the human Frozen Throne campaign and the other was Azure Tower Defense.